Nautilus Drydocks ALVIN (3D printed)

[Subculture]

Some shaft seal housings are available ready made, but 5mm may prove tricky.

You can simply use a simmerring, which is Freudenberg's trade name for a small oil seal. They're just a press fit into a suitably sized hole. e.g. https://www.aliexpress.com/item/1005...Cquery_from%3A

[gboxwood]

That seems doable. Thank you for the pointer, as usual.

[gboxwood]

I was learning from another project I'm running in parallel and I realized I could make the electronics tray much stiffer and more organic in shape.

I took the time to model it as I'm still waiting for the Viper ESC's. I will print it as soon as the ESC's come in (I want to include them in the 3D model before I push play).

ALVIN-031 by Giacomo Bosso, su Flickr

[Albacore 569]

Beautiful work - following with interest.

Has anyone ever considered making the newer ALVIN configuration with the smaller propellers aft? It looks looking further she has had now an even more extensive 3rd upgrade.

https://tahmoh.artstation.com/projects/8lz2gE

[gboxwood]

Nice pictures Albacore. And thank you!

The new thruster configuration would make it a far more interesting boat to drive I would say, with many options to keep your thumbs busy...

The challenge would be finding properly sized R/C units that will not drive the size of the model beyond reasonable. That is, if you want to keep those thrusters scale in proportions.

Something to think about.

[Subculture]

A large scale Alvin could perhaps incorporate motors inside the shrouds.

Would be nigh on impossible for a smaller scale though, so I would look at making an internal prop with a ring around the outside edge incorporating a crown gear.

A small pinion at right angle could then drive the crown gear and prop. Very compact and allows a larger motor which can be tucked inside the boat.

[He Who Shall Not Be Named]

Nice pictures Albacore. And thank you!

The new thruster configuration would make it a far more interesting boat to drive I would say, with many options to keep your thumbs busy...

The challenge would be finding properly sized R/C units that will not drive the size of the model beyond reasonable. That is, if you want to keep those thrusters scale in proportions.

Something to think about.

Instead of multiple motors inside driving little thruster rotors, turn each 'thruster' into an eductor type propulsor. Just one big water pump inside, plumbed with discharge lines to each eductor. Only working parts -- other than the pump itself -- would be a pinch valve at each line leading from pump to eductor. Make it a centrifugal type of pump so it won't lock up when all discharge hoses are isolated.

As a working diver we would sometimes 'fly' an eductor equipped patch around using the thrust produced by the eductor discharge (good way to get embolized or pinched but was good fun when the Supervisor and Master Diver weren't looking).


David

[gboxwood]

Gentlemen,

it is time for an update since a lot has happened since my last post (or at least, that's how it feels on my end).

I printed the new electronics tray, at first as a single piece...

Senza titolo by Giacomo Bosso, su Flickr

... then as a two-parts design:

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

I particularly liked the way the motor fit in it but it is going to change (see a couple of posts further):

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

[gboxwood]

The VIper Marine 15 ESC's arrived and I swapped them with the old ones. Some re-wiring took place to try and tidy things up:

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

Cylinder was fitted and everything seemed to work nicely:

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

[gboxwood]

Next came the upper cylinder, the ballast tank.

I left it 300mm long for the moment and I provided an internal anti-slush assembly in the form of 4 bulkheads with holes held together by 4mm carbon rods:

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

[gboxwood]

The two together for the first time:

Senza titolo by Giacomo Bosso, su Flickr

The ballast tank holds 1 air bottle (500ml) on each side:

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

[gboxwood]

Next was my driveshaft dry seal strategy: a bunch of readily available parts as per picture (O-rings not shown):

Senza titolo by Giacomo Bosso, su Flickr

And the really nice idea by Bob about bringing servo contacts through a bulkhead:

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

In this case, I made a separate plug because I retrofitted it. I also believe that the plug is a good thing in case one pin breaks: it will be much easier to drill the entire plug out and refit a new one this way.

Senza titolo by Giacomo Bosso, su Flickr

[gboxwood]

Dryseal assembly fitted:

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

Ready for final assembly:

Senza titolo by Giacomo Bosso, su Flickr

[gboxwood]

Completing the dryseal from the outside:

Senza titolo by Giacomo Bosso, su Flickr

Initial idea: O-ring + bushing + O-ring + threaded cap

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

More on this later...

[gboxwood]

First checks inside the hull:

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr

Senza titolo by Giacomo Bosso, su Flickr